Re siteing of cities - as ive only ever played vanilla civ cannot comment on the other games and how they are won, but on vanilla civ it is only 3 situations that get you your final score.

1. Future tech - so irrelevant and such a nothing to the final tally not worth wasting your time on.

2. Happy people - building temples, marketplaces etc helps immensely.

3. Land. The single most important item I believe.  Securing more land means more cities, which means as you acquire the Great Wonders that other civs so brilliantly built for you, you get happy citizens which doubly adds to your final score.

So if land or area of control is the most important then shoving a city anywhere is a great advantage. I dont worry too much about the Fat X design as my defence is based on a mobile attack.

(I dont bother building any defenders until say some muskets and then some riflemen leading upto guys I can upgrade to infantry.  Never build spearmen, total waste of time and resource. Build swordsmen instead.  Attack value of 3 and defence value of 2 [same as spear]and gives you a group who can attack as well as defend, depending on the situation)

As I play a world domination type strategy I need plenty of cities to be settler factories.  If they are only a 1 gold per turn city then I rarely both paying for or spend the time building an aquaduct as a temple is also required. I just raid them for settlers every 6-10 turns.

now the problem with that is if the city is simply lacking of food and has zero growth, than adding a worker or settler may not always work. The food production may not support an extra citizen. it really depends.